Overall, Bayern Munchen has better squad depth than Galatasaray, but you need to pay attention to how many Munchen players are in the treatment room. Even though I personally also believe that Munchen can win the match, Galatasaray should not be underestimated because they have a complete squad, because Ziyech will most likely be available again. Tuchel must be fully alert to Galatasaray because they managed to beat Man United at Old Trafford, so they have confidence and a good mentality for now.
Not underestimating Galatasaray is the most important thing for Bayern Munich because Galatasaray could cause an unexpected surprise in their home match, besides that, Galatasaray has also beaten the English team so Bayern Munich has to take this into consideration. Because underestimating opponents in the Champions League is a mistake for any team and Tuchel will of course really pay attention to this because Bayern Munich fully intends to continue dominating the Champions League since this group stage.
The position of Group A standings is now led by Munchen with complete wins, and I think it will remain like that until the group phase matches end. This means that Munchen has a big chance of winning Group A, while the runner-up still has a chance of being contested by three other teams, Galatasaray, Copenhagen and United.
I am sure that Galatasaray will get the opportunity for the runner-up position because currently Galatasaray already has the capital points to stay in the runner-up position. Meanwhile, the other two teams still don't have more points to win the runner-up position and even Manchester United themselves still don't have any points at all in Group A.